I realized recently that the button on my gearshift doesn't do anything. I can shift from P->D and back again without pressing it. It is needed to shift from D->B, but not B->D. Obviously, This is not correct, and kind of worry's me a bit, because its possible to shift into park without pressing it. Not that I make a habit of hitting the shift handle a lot. I'd assume this is not a super fun fix, but I'm wondering if I need to worry about it much, and how id go about fixing it.
Here's what the book says is s'posed to happen, so yeah, yours is being weird: The shift out of P is supposed to require both holding the button, and pressing the brake pedal. Does the brake pedal interlock part still work? Or are you able to shift from P without holding the button and without holding the brake? You have an oldish car by this point that's seen a lot of shifts of that lever, so I could believe if something has worn out. The usual thing I remember reading about here with old gen 1s is when the grommet attaching the park cable wears out (so then you can move the lever but either can't really park or can't really unpark, I forget which way that usually went). There are threads about that you can find here with a search. People did come up with workable fixes for that. The repair manual just tells how to remove the whole shift selector assembly or reinstall it, but not how to take it apart or repair it. Toyota would've just said to replace it with a new one. Probably you'll get your best practical info by searching up the threads from folks who worked out fixes for the park cable, even though that's not exactly what's happened to yours.
